A LoRaWAN Carbon Monoxide Measurement System with Low-Power Sensor-Triggering for the Monitoring of Domestic and Industrial Boilers

Gases emitted by domestic and industrial boilers significantly contribute to the overall pollution levels of urban environments. Among these gases, Carbon Monoxide (CO) represents a marker of the efficiency of the combustion processes, and the monitoring of its emissions, even if often neglected, is crucial to improve the energy efficiency and the environmental safety within a Smart City context. This paper aims at describing a real-time, remote system for the monitoring of CO emissions of domestic and industrial boilers, based on the use of a low power Long Range Wide Area Network (LoRaWAN) sensor node. In particular, the proposed solution is based on an ad-hoc frontend circuit acting as a power gating system for the rest of the sensor node, exploiting the output of the CO sensor as a trigger to activate the data acquisition and transmission module. Such a solution allows to notably increase the life time of the node, allowing its powering by means of rechargeable Li-Ion batteries. Tests were performed on a real boiler in order to demonstrate the validity of the proposed solution. Power consumption of the sensor node was experimentally measured: theoretical analysis demonstrated an ideal life time for the sensor node up to 2 years and half.